Ti-5Al-5Mo-5V-1Cr-1Fe合金热加工图及其组织演变  

Hot processing map and microstructural revolution of Ti-5Al-5Mo-5V-1Cr-1Fe alloy

作　　者：祖利国[1] 张晓泳[1,2] 李超[1] 周科朝[1] 唐仁波[3] 

机构地区：[1]中南大学粉末冶金国家重点实验室,湖南长沙410083 [2]中南大学冶金科学与工程学院,湖南长沙410083 [3]湖南金天钛业科技有限公司,湖南常德415001

出　　处：《中南大学学报（自然科学版）》2012年第8期2943-2950,共8页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金委员会创新研究群体科学基金资助项目(51021063);湖南省科技重大专项(2010F51004);中南大学前沿研究计划项目(2009QZZD007);中南大学博士后基金资助项目(2009年)

摘　　要：采用热模拟试验机对Ti-5Al-5Mo-5V-1Cr-1Fe合金进行等温压缩试验,获得变形温度为750~900℃和应变速率为0.001~1 s 1时的真应力真应变曲线,并运用修正后的试验数据建立真应变为0.7的热加工图。通过显微组织观察,分析合金的变形机理,确定热变形失稳区。研究结果表明：Ti-5Al-5Mo-5V-1Cr-1Fe合金加工温度范围较宽,当加工温度低于800℃且变形速率大于0.1 s 1时易发生绝热剪切,造成流变失稳;随着变形温度升高,功率耗散因子η有增大趋势,合金的流动软化机制由动态回复逐渐变为动态再结晶,显微组织也随之细化、均匀。The hot deformation characteristics of Ti-5A1-5Mo-5V-1Cr-IFe alloy were investigated between 750-900 ℃ and strain rate range of 0.01-1 s-1 through hot compression tests. The processing map at strain of 0.7 was given according to the corrected data of true stress-strain curves, and the microstructures of deformed specimens were observed. The region of deformation instability and deformation mechanism was abtained from the map. The results show that Ti-5A1-5Mo-5V-1Cr-IFe alloy can be processed in a large temperature range, while adiabatic shear appears at relatively low temperature （〈800 ℃） and high strain rate （〉0.1 s-l）. The power dissipation factor increases with the increase of the temperature, the deformation mechanism transforms from dynamic recovery to dynamic recrystaUization, and the microscopic structure of the alloy is more uniform.

关 键 词：Ti-5Al-5Mo-5V-1Cr-1Fe合金 高温变形 加工图 显微组织 

分 类 号：TG146.2[一般工业技术—材料科学与工程]